Mixing screw

ABSTRACT

An auger for a vertical feed mixer with a lifting surface that is upwardly angle from an inner edge toward an outer edge. A fliting portion to form a part of an auger for a vertical feed mixer, the fliting portion including an outer edge that is positioned higher than a radially positioned inner edge. An auger for a vertical feed mixer that in rotation defines an hourglass shape.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to earlier filed U.S.Provisional Application Ser. No. 61/433,522, filed on Jan. 17, 2011, thedisclosure of which is incorporated herein by reference in its entirety.

BACKGROUND

Conventional vertical feed mixers incorporate a central rotating shaftwith helical fliting or a screw mounted about the shaft. The rotation ofthe shaft rotates the screw so that a lower end of the screw, having aleading edge, will move forward about a base of an interior feed mixinghopper. As the leading edge encounters feed within the hopper, the feedis directed up a ramped face of the screw. As the screw rotates, thefeed rises higher in the screw until in cascades off an outer edge ofthe screw fliting or rises to the upper trailing edge of the screw whereis falls back toward the base of the hopper. The purpose of the screw isto mix the feed and reduce the feed to more uniform particle sizes.

The action of the screw through the feed serves to thoroughly mix thefeed with the hopper so that a uniform ration comprised of multipleingredients, feeds or supplements may be distributed from the hopper.The screw also works to chop larger clumps of feed or silage intosmaller pieces.

It is desirable to improve the ability of the fliting to mix and chopthe feed within the hopper.

DESCRIPTION OF THE DRAWINGS

The accompanying drawing figures, which are incorporated in andconstitute a part of the description, illustrate several aspects of theinvention and together with the description, serve to explain theprinciples of the invention. A brief description of the figures is asfollows:

FIG. 1 is a perspective view of a vertical feed mixer according to thepresent disclosure with a portion of a side wall of a mixing tub notshown for clarity.

FIG. 2 is a top view of the vertical feed mixer of FIG. 1 with thecomplete side wall of the mixing tub shown.

FIG. 3 is a side view of the vertical feed mixer of FIG. 1.

FIG. 4 is a side view of a portion of the fliting of a prior art mixingauger.

FIG. 5 is a side view of a portion of the fliting of a mixing augeraccording to the present disclosure for use with a vertical feed mixer.

FIG. 6 is a side view of a first alternative embodiment of a portion ofthe fliting of a mixing auger according to the present disclosure foruse with a vertical feed mixer.

FIG. 7 is a side view of a second alternative embodiment of a portion ofthe fliting of a mixing auger according to the present disclosure foruse with a vertical feed mixer.

FIG. 8 is a side view of a third alternative embodiment of a portion ofthe fliting of a mixing auger according to the present disclosure foruse with a vertical feed mixer.

FIG. 9 is a side view of a fourth alternative embodiment of a portion ofthe fliting of a mixing auger according to the present disclosure foruse with a vertical feed mixer.

DESCRIPTION

Reference will now be made in detail to exemplary aspects of the presentinvention which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts.

Referring now to FIGS. 1 to 3, a vertical feed mixer 100 according thepresent disclosure includes a tub 102 within which feed for livestock orother animals may be mixed, and a vertical mixing auger 104 mountedwithin tub 102 and configured to be rotated with a vertical shaft or hub51. Shaft 51 may be driven by a motor mounted beneath tub 102 as part ofmixer 100 or may be driven by a transmission motivated by a power takeoff assembly associated with a vehicle that may be attached to mixer100. Tub 102 may be mounted to a frame 106 which may be include one ormore axles 108 for facilitating movement of mixer 100. Frame 106 mayinclude a hitch 110 for engaging a vehicle to move mixer 100 about afarm or feedlot as needed to feed or provide other nutrients tolivestock or other animals.

Before feed is delivered to the animals, a variety of feed constituentsand/or supplements may be added into tub 102 and auger 104 may berotated within the tub to mix into a generally uniform or homogenousblend and chop the feed into a generally uniform size. Once the feed hasbeen prepared, an opening 112 may be provided in a sidewall of tub 102to permit the discharge of the feed. Rotation of the auger may then beused to aid in the uniform distribution of the feed as the mixer ispulled along or as a conveyor carries feed away from the mixer.

It is not uncommon for metallic contaminants to be accidentallyintroduced into of with the feed constituents. Examples of this might bebut are limited to bailing wire from the hay or other fodder bundlingarrangements, or loose parts or pieces of farm equipment or othermachinery. Having such metallic contaminants in the feed is notdesirable as this may injure the animals being fed. A magnet 114 may beincluded within tub 102 along a side wall adjacent a the bottom 116 oftub 102. Such a location will allow the magnet to act on feed as it isbeing moved about by a lower leading edge 118 of auger 104. In thislocation, the mixed feed may make multiple passes adjacent magnet 114 asthe feed is mixed and then rotated by the auger for delivery throughopening 112. The more passes the feed makes past magnet 114, the betterthe opportunity for any metallic contaminants to be removed from thefeed and held to magnet 114 for removal when the tub is empty.

It may be preferable to have magnet 114 mounted above the bottom of thetub but adjacent the bottom of the tub and slightly above a height ofthe leading edge of the auger. Thus positioned, as feed is lifting fromthe bottom of the tub by the auger, and forced outward on the liftingsurface of the auger, the feed will be forced to pass close to magnet114 but will not be pressed against the magnet so as to not dislodge anymetal already adhering to the magnet. It may also be preferable to havemagnet 114 mounted at a position away from the discharge opening toensure that feed being pressed toward the discharge opening does notdrag against the magnet and dislodge metal already adhering to themagnet as the mixed feed is discharged.

Referring now to FIG. 4, a fliting portion 50 of a prior art auger isshown. Fliting 50 may be used as a portion of an auger within a verticalfeed mixer configured similarly to mixer 100. Fliting portion 50 isconfigured such the an inner edge 154 (adjacent shaft 51) of an upperradial 156 is at generally the same height as an outer edge 158.Similarly, an inner edge 160 of a lower radial 162 is generally at thesame height as an outer edge 164. Between the inner and outer edges andthe upper and lower radials is defined a surface 152 on which the feedwithin the tub is lifted as the auger rotates. As the feed is lifted upon the auger, the feed will cascade off an outer circumferential edge166 that runs between outer edges 158 and 164. As can be seen in FIG. 4,outer circumferential edge 166 decreases in radius from outer edge 164to outer edge 158. This further promotes the feed cascading off theauger and back toward bottom 116 of tub 102.

Referring now to FIG. 5, a fliting portion 150 of an auger for avertical feed mixer according to the present disclosure is shown whichis configured to retain feed on the auger longer to promote mixing andchopping of the feed as the auger rotates within tub 102. Flitingportion 150 includes an upper radial 156 with an inner edge 154 adjacentshaft 51 and an outer edge 158. Outer edge 158 is positioned higherabove tub bottom 116 relative to inner edge 154. Similarly, a lowerradial 162 has an inner edge 160 adjacent shaft 51 and an outer edge164, wherein outer edge 164 is positioned higher above tub bottom 116relative to inner edge 160. As shown a lifting surface 152 of flitingportion 150 is generally consistently sloped upward from the inner edgeto the radially positioned outer edge at an angle indicated in the FIG.as “TIP ANGLE.”

It is anticipated that the TIP ANGLE formed by the fliting with respectto a radial line extending perpendicular from the shaft or tubing can bebetween approximately two (2) degrees and approximately ten (10)degrees. Current experience has shown for certain feeds and mixes offeeds, approximately five and one half (5.5) degrees is preferable. Thisangling of the fliting has proved to keep the feed within the hopper onthe flite longer and promotes more thorough and quicker mixing of thefeed as well as more rapid reduction of size of the elements of thefeed.

Fliting portion 150 of FIG. 4 is shown with the entire flite having auniformly tilted upper surface 152. It may be desirable to have theleading edge of the fliting configured to be generally parallel to thebase of the hopper so that more feed from the base of the hopper islifted and mixed. The hopper floor may be sloped to match the slope ofthe flite or the leading edge of the flite may be flattened to generallymatch the shape or contour, if any, of the base.

Alternatively, it is anticipated that a fliting portion according to thepresent disclosure may include a generally flat portion generallyparallel to the bottom of the tub while still maintaining an outer edgeraised within respect to a radially positioned inner edge. While theupper surfaces of the fliting portions of the FIGS. are shown asgenerally planar and consistent in angle from leading edge to trailingedge, it is anticipated that the top surface of the flights may vary inangle. The variation in angle may be between the leading edge andtrailing edge as the flite transitions upwards, or may be variable fromthe inner edge to the outer edge. Alternatively, the variation of anglemay be a combination of both top to bottom and inner edge to outer edge.

FIGS. 6 to 8 illustrate different configurations of fliting portionsaccording to the present disclosure. FIG. 6 illustrates an alternativeembodiment of a fliting portion 250 configured for mounting about ashaft 51. An upper radial 256 includes an inner edge 254 adjacent shaft51 and an outer edge 258 positioned generally above inner edge 254. Alifting surface 252 extends between the inner and outer edges and may begenerally parallel to the tub bottom except adjacent outer edge 258where a lip or angled portion 257 extends at an angle upwards to outeredge 258. As shown, angled portion 257 may formed integrally formed withfliting portion 250.

A lower radial 262 may include an inner edge 260 adjacent shaft 51 andan outer edge 264 positioned generally above inner edge 260. Angledportion 257 may also extend from generally parallel lifting surface 252up to outer edge 264. Outer edge 258 and outer edge 264 may be generallythe same height above inner edge 254 and inner edge 260, respectively,indicated in FIG. 6 by “A.” Angled portion 257 may have a widthindicated in FIG. 6 by “B” and while the angle of angled portion 257 maybe greater than the angle described above, it is anticipated that theeffective angle formed between the respective inner and outer edgesshould be between two and ten degrees.

FIG. 7 illustrates a third alternative embodiment of a fliting portion350 configured for mounting about a shaft 51. An upper radial 356includes an inner edge 354 adjacent shaft 51 and an outer edge 358positioned generally above inner edge 354. A lifting surface 352 extendsbetween the inner and outer edges and may be generally parallel to thetub bottom except adjacent outer edge 358 where a lip or angled portion357 extends at an angle upwards to outer edge 358. As shown, angledportion 357 may be a separate piece that is joined to fliting portion350, such as by welding or bonding.

A lower radial 362 may include an inner edge 360 adjacent shaft 51 andan outer edge 364 positioned generally above inner edge 360. Angledportion 357 may also extend from generally parallel lifting surface 352up to outer edge 364. Outer edge 358 and outer edge 364 may be generallythe same height above inner edge 354 and inner edge 360, respectively,indicated in FIG. 7 by “A.” Angled portion 357 may have a widthindicated in FIG. 7 by “B” and while the angle of angled portion 357 maybe greater than the angle described above, it is anticipated that theeffective angle formed between the respective inner and outer edgesshould be between two and ten degrees.

FIG. 8 illustrates a fourth alternative embodiment of a fliting portion450 configured for mounting about a shaft 51. An upper radial 456includes an inner edge 454 adjacent shaft 51 and an outer edge 458positioned generally above inner edge 454. A lifting surface 452 extendsbetween the inner and outer edges and may be generally parallel to thetub bottom except adjacent outer edge 458 where a lip or wall portion457 extends generally upwards to outer edge 458. As shown, wall portion457 may be a separate piece that is joined to fliting portion 450, suchas by welding or bonding. Alternatively, wall portion 457 may be formedintegrally with fliting portion 450.

A lower radial 462 may include an inner edge 460 adjacent shaft 51 andan outer edge 464 positioned generally above inner edge 460. Wallportion 457 may also extend from generally parallel lifting surface 452up to outer edge 464. Outer edge 458 and outer edge 464 may be generallythe same height above inner edge 454 and inner edge 460, respectively,indicated in FIG. 8 by “A.” It is anticipated that the effective angleformed between the respective inner and outer edges should be betweentwo and ten degrees.

It is understood that the higher outer edge improves the ability of theflite to hold feed longer and transition the feed higher within thehopper on the flite to improve the mixing and chopping operation of thevertical mixer beyond the performance of the conventional planar flites.

Referring now to FIG. 9, a further embodiment of an auger 550 is shownconfigured for use with a vertical feed mixer such as mixer 100. Auger550 may be comprised of multiple fliting portions. As shown by thedashed lines, auger 550 in rotation defines an hourglass shape. A lowerportion 570 may be configured with a leading edge 578 configured tocooperate with the tub bottom to effectively engage and lift feed withintub 102. An intermediate portion 572 may extend between lower portion570 and an upper portion 574 having an upper trailing edge 576. Portions572 and 574 may be essentially mirror image elements that define anarrower auger shape 580 at a joint line 581 between the two portionsbetween wider auger shapes 582 and 584 above and below narrower shape580. It is anticipated that fliting portions as shown in FIG. 9 mayinclude the raised outer edge as described above. It is furtheranticipated that the fliting portions shown in FIG. 9 may be configuredwith flat lifting surfaces as described in the prior art above.

As shown in FIGS. 1 to 3, an auger according to the present disclosuremay be made of multiple fliting portions that define a generally conicalshape, where the top of the auger is inwardly positioned with respect tothe top of the side wall of the tub. The gap between the auger and theside wall adjacent the top of the auger is where bridging may occur. Thehour glass shape defined by the rotation of auger 550 may serve to allowbetter operation of mixer 100. It is not uncommon for bridging of feedmaterials to occur near a top of tub 102 such that the feed materials donot descend into the tub to be mixed and chopped by the auger. Thesefeed materials may then block the entry of other feed materials into thetub for mixing and chopping. An operator may need to climb onto themixer and physically break up the bridged materials, which may be adangerous and slow down the feeding operation. Trailing edge 576 extendsoutward toward the side wall of the tub and also upwards to dig into thebridged material and encourage it to fall into the tub without the needfor user intervention.

While auger 550 is shown with two fliting portions being generallymirror images of each other for ease of design and manufacture, it isnot necessary to have different fliting portions shaped similarly toeach other. An auger according to the present disclosure may have onlyan upper and a lower fliting portion and still define the generalhourglass shape and a trailing edge extending up into the bridging zoneto dislodge feed materials. The two fliting portions may be similarshaped or may be unique with respect to each other. Alternatively, anauger may be made of more than three fliting portions, one or all ofwhich may be uniquely shaped relative to the others.

While the invention has been described with reference to preferredembodiments, it is to be understood that the invention is not intendedto be limited to the specific embodiments set forth above. Thus, it isrecognized that those skilled in the art will appreciate that certainsubstitutions, alterations, modifications, and omissions may be madewithout departing from the spirit or intent of the invention.Accordingly, the foregoing description is meant to be exemplary only,the invention is to be taken as including all reasonable equivalents tothe subject matter of the invention, and should not limit the scope ofthe invention set forth in the following claims.

1. A fliting portion for use as a vertical mixing auger in a verticalfeed mixer, the vertical feed mixer including a rotating vertical shaftmounted within a tub, the fliting portion comprising: a lower edgepositioned toward a bottom of the tub and a trailing edge positionedrelatively higher within the tub; a generally helical form extendingbetween the leading edge and the trailing edge and positioned about therotating vertical shaft, the generally helical form defining a feedlifting surface; the helical form extending outward from an inner edgeadjacent the shaft to an outer edge positioned away from the shaft; theouter edge positioned relatively higher away from the bottom of the tubas compared to a corresponding inner edge generally along a radiusextending from the shaft outward.
 2. The fliting portion of claim 1,further comprising the lifting surface extending generally evenlybetween the inner edge and the outer edge.
 3. The fliting portion ofclaim 1, further comprising the lifting surface extending generallyevenly toward the outer edge and an outboard portion of the liftingsurface adjacent the outer edge extending upward to the outer edge. 4.The fliting portion of claim 3, further comprising the outboard portionof the lifting surface being an upward angled surface relative to theinner portion of the lifting surface.
 5. The fliting portion of claim 3,further comprising the upward extending outboard portion of the liftingsurface being integrally formed with the lifting surface.
 6. The flitingportion of claim 3, further comprising the upward extending outboardportion of the lifting surface being made of a separate element andattached to the lifting surface.
 7. The fliting portion of claim 3,further comprising the upward extending outboard portion comprising awall portion.
 8. The fliting portion of claim 1, further comprising aradial line from the inner to the outer edge defining a tip angle, thetip angle being within a range from approximately two degrees toapproximately ten degrees above horizontal.
 9. An auger for a verticalfeed mixer, the vertical feed mixer including a rotating central shaftabout which the auger is positioned, the auger comprising: at least onefliting portion, the fliting portion comprising: a lower edge positionedtoward a bottom of the tub and a trailing edge positioned relativelyhigher within the tub; a generally helical form extending between theleading edge and the trailing edge and positioned about the rotatingvertical shaft, the generally helical form defining a feed liftingsurface; the helical form extending outward from an inner edge adjacentthe shaft to an outer edge positioned away from the shaft; the outeredge positioned relatively higher away from the bottom of the tub ascompared to a corresponding inner edge generally along a radiusextending from the shaft outward.
 10. The auger of claim 9, furthercomprising a plurality of fliting portions cooperating to form a singlelifting surface extending from a lower leading edge to an upper trailingedge.
 11. The auger of claim 9, further comprising, the auger inrotation defining an hourglass shape with a narrower portion in themiddle and wider portions above and below the narrower portion.
 12. Theauger of claim 10, further comprising the auger in rotation defining anhourglass shape with a narrower portion in the middle and wider portionsabove and below the narrower portion, with the narrower portion definedat a join line between two adjacent fliting portions.
 13. The auger ofclaim 12, further comprising the adjacent fliting portions havinggenerally mirror image shapes with respect to each other.
 14. Thefliting portion of claim 9, further comprising a radial line from theinner to the outer edge defining a tip angle, the tip angle being withina range from approximately two degrees to approximately ten degreesabove horizontal.
 14. A vertical feed mixer comprising: a tub: an augermounted generally vertically within the tub about a generally verticalshaft, the auger including a lower leading edge extending from the shaftadjacent a bottom of the tub and an upper trailing edge extending fromthe shaft opposite the bottom of the tub; the auger having a liftingsurface with an inner edge adjacent the shaft and an outer edge which isgenerally higher than the inner edge along a line extending generallyradially from the shaft, the line defining an angle above horizontal ofbetween approximately two degrees and approximately ten degrees; amagnet mounted to a side wall of the tub adjacent the bottom of the tuband just above the leading edge of the auger.
 15. The vertical feedmixer of claim 14, further comprising the auger comprised of a pluralityof fliting portions.
 16. The vertical feed mixer of claim 14, furthercomprising the auger in rotation defining an hourglass shape with anarrower portion and wider portions above and below the narrowerportion.
 17. A vertical feed mixer comprising: a tub: an auger mountedgenerally vertically within the tub about a generally vertical shaft,the auger including a lower leading edge extending from the shaftadjacent a bottom of the tub and an upper trailing edge extending fromthe shaft opposite the bottom of the tub; the auger in rotation definingan hourglass shape with a narrower portion in the middle and widerportions above and below the narrower portion; a magnet mounted to aside wall of the tub adjacent the bottom of the tub and just above theleading edge of the auger.
 18. The vertical feed mixer of claim 17,further comprising the auger extending from an inner edge adjacent theshaft to an outer edge, the outer edge being positioned above thecorresponding inner edge so that a line extending generally radiallyfrom the inner edge to the outer edge forms an angle from horizontal offrom approximately two degrees to approximately ten degrees.